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When the preceding statement is executed, a prompt box will appear in the web browser asking
                  to input the age. By default, the input taken by the prompt( ) method is considered as a string in
                  JavaScript.
                  If you want to perform some mathematical calculations, then we need to convert the value into an
                  integer by using the parseInt( ) method. We can use the parseInt( ) method in the following way:

                  var num = parseInt(prompt("Enter first number: "));
                  The document.write( ) method is used to display output on the web page.

                  For example:

                  document.write("Hello from JavaScript");
                  The preceding statement will display the message "Hello from JavaScript" on the web page. Let us
                  create a web page to calculate the sum of two numbers in JavaScript.

                  <HTML>

                  <HEAD>
                  <TITLE> Statements in JavaScript </TITLE>
                  </HEAD>
                  <BODY>
                  <SCRIPT type="text/javascript">
                  var a = parseInt(prompt("Enter first number: "));
                  var b = parseInt(prompt("Enter second number: "));

                  var c;
                  c = a + b;
                  document.write("Sum of a and b is: ");
                  document.write(c);
                  </SCRIPT>

                  </BODY>
                  </HTML>
                  Save the file with .html extension and open the web page in web browser. You will get the following
                  output:

























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